1. Field of Invention
The present invention relates to a valve device, and more particularly to a vacuum valve device for a bag and that allows the bag to be deflated and sealed so items in the bag are vacuum-packed.
2. Description of Related Arts
Plastic bags are non-permeable to water and gas and are used widely to package and preserve items for example quilts, carpets, clothes, and foods such as fish, meat and vegetables.
A conventional plastic bag has an opening and a seal mounted on the opening. After items or foods are packaged in the plastic bag, people may squeeze inside air out of the plastic bag and then close the seal to vacuum-package the items or foods. However, manually squeezing the bag cannot entirely discharge inside air out of the plastic bag. Remaining air inside the plastic bag will oxidize the items and decompose the foods.
To solve the problem that the air remains in the plastic bag, an improved plastic bag with an un-detachable vacuum valve is developed. The vacuum valve is melted and mounted securely on the plastic bag and may be connected to a vacuum pump. The vacuum pump may pump inside air thoroughly out of the plastic bag through the valve so the plastic bag may finely package and preserve items or tools.
However, the plastic bag with the valve has a high cost. Furthermore, the plastic bag has a short life-span and needs to be discarded soon due to the plastic bag is damaged easily or smells after packaging foods such as meat and fishes. People are unwilling to buy such plastic bags with a high cost and a shots life-span. Therefore, the plastic bag with the un-detachable valve is unmarketable.
To overcome the shortcomings, the present invention provides a vacuum valve device for a bag to mitigate or obviate the aforementioned problems. The vacuum valve is able to detachably coupling with most of the bags for storing food, clothes, and others, so that the vacuum valve is able to be detached from a worn out bag to incorporate with another bag, so as to economically re-use the vacuum valve.
In order to detachably couple a detachable vacuum valve for vacuuming the air in a non-permeable bag, the user either has to make a hole through the sheet of bag that approximately matching the air outlet of the vacuum valve, so that the air is able to flow to the air outlet via a valve tube through the hole on the bag.
However, the hole is normally not accurate enough to match an opening of the air outlet, so that the bag may not be able to completely seal the cavity through the vacuum valve, so as to reduce the ability of isolating the object stored in the bag from the air or the likes. Therefore, the hole may be too small for the valve tube passing through, or too big that the vacuum valve is unable to completely seal the bag in an air-tight manner.
How to detachably mount the detachably vacuum valve to the bag is another major issues to seal and tight the cavity of the bag through the hole thereon. Accordingly, when the detachably vacuum valve is mounted at the bag, bag may also be twisted while making a hole on the bag or while coupling the valve with bag via a non-fixed hole on the bag. In order to tightly couple the detachably vacuum valve, the detachably vacuum valve must be large enough for being tightly held by two hands of the user. Therefore, it is relatively easier to apply a rotational force to tightly seal the vacuum valve. It increases the volume of the vacuum valve, and reduces the storage space within the storing bag.